1. Field of the Invention:
The invention relates to water closets of the type having a flush tank and outlet valve assembly, and particularly to devices adapted for placement in water closet flush tanks to effect savings of water during flushing.
2. Description of the Prior Art:
A common type of water closet which has widespread household, hotel, motel, and institutional use, employs a rectangular flush tank in which a valve mechanism is mounted. Recognizing that a surplus of water is often expended during the flushing operation of a conventional water closet employing such a flush tank, the prior art has sought various means with which to effect savings of water normally consumed. One well-known approach has been to provide the user with a choice of two volumes of water depending on the matter to be flushed and is known as the dual flush type. This is shown typically in U.S. Pat. No. 3,538,519 which includes mechanical flush volume controls and refers to earlier related art.
Another broad approach, and that which is pursued by the present invention, is that of installing an auxiliary wall structure in the tank which is adapted to form an open-ended column around the valve so that water surrounding the column is prevented from being flushed and is saved in each flushing operation. This broad concept apparently first appeared in 1919 in U.S. Pat. No. 1,323,703. A modification of the same broad concept appears in U.S. Pat. No. 3,041,630 which is directed to an auxiliary structure having an adjustable column height.
The most recently discovered patent involving the same broad concept is U.S. Pat. No. 3,259,918, which provides a rigid, closed wall member that forms an open-ended rectangular box which surrounds all of the internal tank mechanism including the inlet and outlet valve assemblies, and which is adhesively secured to the bottom wall to form a water column designed to save the amount of water, during each flush, which surrounds the column.
Directed to the same broad concept is copending application Ser. No. 105,032 which teaches the use of a flexible four-walled box structure having open ends and which can be bent, assembled and installed in a closet water tank without removing or altering any internal plumbing parts, to provide an open-ended column immediately surrounding the flush valve mechanism. Copending application, Ser. No. 191,228, teaches the use of a flexible, five-walled, U-shaped device which is sealed against the tank bottom and immediately surrounds the flush valve mechanism and is held in place by spring plunger rods pressing against a side of the tank. This type of construction adapts to a wider variety of existing flush tank configurations than had formerly been possible. All of the mentioned copending applications are directed to the concept of saving water during flushing by means of an inexpensive, flexible-walled auxiliary column which immediately surrounds a flush valve in a water closet flush tank. During bowl evacuation, only the water contained above the column or within the column is permitted to be discharged. The water lying outside and below the top of the column is retained. Although the devices and methods of the aforementioned copending applications are believed to be unique and to have been the first teaching of a convenient, inexpensive and effective means of saving water during flushing without requiring disassembly of the tank plumbing, a need for further improvement has been revealed.
While the previously mentioned copending applications have been concerned with inventions having proven success in a majority of plumbing installations, it is recognized that there still exists a small yet significant number of water closet flush tanks wherein the above mentioned inventions may not prove entirely satisfactory without small modification to the invention apparatus. In particular, unconventional placement of plumbing parts within the flush tank often prohibits the use of water saving devices of the prior art. It is therefore an object of the present invention to provide an inexpensive, easily installed, efficient water saving device adapted for use in nearly all types of water closet flush tanks. In addition, due to the wide range in flush tank configurations, water saving devices of the prior art and as described in the previously mentioned copending applications, often require minor adjustment and modification to yield the optimum flow and volume characteristics. Frequently this entails alterations not consistent with the original design and function. It is therefore another object of the present invention to provide a water saving device suitable for use in water closet flush tanks, which can be readily adjusted while in the tank to give the desired flushing characteristics.
Other objects and advantages of the present invention will be perceived in the description and appended claims which follow.